Electric switch



Aug. 16, 1932 J. R. COOK ELECTRIC SWITCH Original Filed Deo. 4. 1922 2Sheets-Sheet l 35 5l zz 3@ l Z0 .l Z z3 l K5 7 /5 j. l0 /4 A ug. 16,1932. J. R. cooK 1,372,122

l y ELECTRIC SWITCH -Orginal FiledkDeo. 4. 1922 2 Sheets-Sheet 2 Ten-farfymww C Patented Aug. 16, y1932 UNITED STATES PATENT OFFICE l W J' OELB.. COOK, 0l' CLEVELAND, OHIO, ASBIGNOB, BY HEBNE ASSIGNMENTS, TOWESTING- HOUSE ELECTRIC & IANUFACTUBING COMPANY, A CORPORATION 0F PENN-'SYLVANIL morale swrrcn Application led December 4, 1982, Serial No.604,762. Renewed January 31, v1930.

This invention relates to circuit breakers and is particularly concernedwith that ty e wherein an electro-responsive tripping evice may releasea circuit closer responsive to changes in the value of the current,andin- K cludes manual means for resettingthe tripping device andclosing the circuit. A convement and frequent use of the invention is inconnection with a manually operated circuit closer, normally governingthe circuit to open and close the same, as desired,

e but allowing the circuit breaker to act un- N and circuit breaker inseries.

I consider it advantageous to so connect the circuit breaker and switchmechanism;

that the operation of the switch may close 4the circuit breaker, andresetthe latch after Vit has been opened, and thereafter allow theVmanually operated switch to govern the circuit through an indefinitenumber of makes and breaks, causing opening and closing of the circuituntil an abnormal condition occurs. Such a general arrangement isillustrated in my copendingl application filed Sept.,18, 1922, SerialNo. 588,755.A

' An object of this invention is to provide a simple and effectivearrangement of the operating connectionbetween switch operatingmechanism and the electroresponsive ciricuitv closer. Further objectsinclude compactness of the elements comprising the circuitcloser,\cheapness of manufacture, certainty of operation, while havingno parts subject to-excess Wear or'likely to get out of order. p

In the drawings, I have shqown an arrangement of a rotary snap switch ofwell known carrying current and adapted upon an overload to renderactive a shunt through the solenoid, thereby tripping the circuitbreaker, and I have so connected the snap switch member with the circuitbreaker elements that subsequent turning may reset the snap switch.

One of the objects of the present invention is to provide a simplearrangement of latching mechanism whereby if the abnormal circuitcondition, that is for example, the overload still'exists, the circuitbrea er can not be reset until the current is normal. Another specificobject is to so arrange the circuit connections through vthe solenoidwith relation to thefcircuit 'breaker that the current through ythecircuit breaker is never more than momentary,` that is, it can not passthrough the solenoid longer than a period just sufficient to cause it toperate to open the circuit breaker. This vallows the use of a small,and therefore cheap, solenoid having light windings.

In the drawings, Fi 1 is in the nature of a side elevation of t emanually operated snap switch and electrofresponsive switch mounted onthe same base, the housing for each being shown in section;'Fig. 2 is asubstantially axial section through the rotary snap switch andcorresponding parts of` the electroresponsive circuit brea er; Fig. 3 isa sectional detail showing the arrangement of the solenoid actuating thetrippin mechanism; Fig. 4 is a sectional lan of t e electro-responsivevvcircuit brea er mechanism showing its housing in section; Fig. 5 is asimilar view showing the parts 4ofthe circuit Ybreaker in open circuitposition; Fig. 6 is a -sectionaljplan of the snap switch showing itshousing in section; Fig.l 7 1s a sectlonal plan showing the step by stepmechanism ofv the snap swltch; Fig. 8 is a sectional detail takensubstantially on the line 8-8 of Fig.

4, showing thethermostatic electric conduc tor in its closed position;Fig. 9 is a similar view showing the open position thereof; On

design, associated with the circuit breaker, Fig. 4 is shown a brokenline indicating the construction governed by latch mechanism plane ofthe section of Fig.l 2; the plane of controlled by a solenoid in turn,controlled the section'through the solenoid is indicated byL a currentresponsive member,- normally by the line 3--3 of Fig. 4. I

' 10 embraced by the spring 11, engaging one Y A suitable base for themounting of the parts consists of a block 1, preferably rigid with aplate 2, somewhat larger in diameter, while the block 1 forms a bearingfor the shaft 5 having the usual hand knob 3 for a snap switch as shown.As is customary in switches of this type, the shaft 5 is provided with aprojection or cam G allowing a relative movement, and a rotatablestopwasher 7 adapted to engage projections 8 on a plate 9. This is shownparticularly in Fig. 7, these parts appearing in section in Fig. 2. Onthis shaft 5 is provided the usual sleeve of the notches in the fiange12, while the other end engages the carrier 13 for the switch blades 14,adapted in one position to bridge between contacts 15 and 16, and inanother position, brought about by a quarter turn of the knob, to standaway from the contacts, that is, at right angles to the position in Fig.6. The shaft 5 is shown as projecting through the block 1 and plate 2and as carrying rigidly on its end a two part cam 20, adapted to engageaprojection 21 formed rigid on a circuit breaker blade 22, shown aspivoted at 23 and adapted in one position, as shown in Fig. 4, to engagea contact 25.V

In order to make clear the function of the severai parts, the path ofthe current may be traced through both switches as follows: The currentmay pass, say from one of the lead wires 26 to the terminal 15 as shownin Fig. 2 and thence through the switch blades 14 to the terminal 16,through a wire 28 to the pivot 23, then through thepivoted blade 22,Contact 25, and thence through a thermostatic bar designated 30, to acontact strip 32; and thence to the other lead wire 26.

The thermostatic bar preferably is made up of two strips ofmetal securedtogether and adapted when carrying an excessive current to become heatedconsequent upon the resistance offered, the heat causing the barvwhichis rigid at one end, as shown in Figs. 8 and 9, to raise its contactfrom the member 32, thus interrupting the lnormal flow of the current,by opening the normal circuit. rihis shunts the current as will now bedescribed, through a solenoid governing a latch for the switch blade22.4

The circuit breaker blade 22 is urged to open by any 'suitable yieldingmeans such as a spring 35, shown as attached at one end to the blade andat the other to a pin or post, or the like 36 which may be rigid. withthe plate 2. In the position shown in Fig. 4, this blade is held in enagement With the contact 25 by a latch mem er consisting of a bar 40,pivoted at 41 and having a projecting shoulder adapted to engage the endof the blade or bar 22. The'end of the bar 40 embraces a reduced portionof a pin 45 attached to the solenoid core as shown particularly in Fig.3. This reduced portion pro- `vides a. shoulder on the core pin ateither side of the bar 40.

The solenoid may comprise the usual coils indicated at 46 in the form ofa spool mounted upon supports 48 carried on the plate 2, the core beingsurrounded by a sleeve 49 in which the solenoid may slide. rl`he corepin 45 is preferably of nonmagnetic material while the core 50 is ofsuitable iron. The pin forms a reduced extension projecting through anopening in one end of the support, thus providing a space for a spring52, normally urging the core to the right. The coil is shown asconnected in parallel with the thermostatic bar 30 by wires designatedleading to the contacts 25 and 32 so that when the thermostatic bar iselectrical-` ly disconnected the solenoid forms a shunt, bridging thisbreak in the circuit with the result that the heavy portion of the core50 tends to center itself within the core 4G. The first part of themovement being idle until the inner shoulder engages the bar 40 afterAthe core has attained some momentum, whereby the bar 40 is forcibly andcertainly disengaged from the circ-uit breaker blade 22. Thethermostatic bar 30 is of such proportions that, when it is closed, themajor portion of the current through the circuit-breaker-switch blade 22passes through the thermostatic bar, and very little current passesthrough the solenoid 4G. However', when the thermostatic bar, whichshunts the solenoid 4G,

moves out of engagement with the contact 32, all of the current throughthe circuit breaker passes through the solenoid coil and causes it totrip the circuit breaker to open position.

Since the solenoid coil is carrying all of the current passing throughthe blade 22 at the time the circuit therethrough is beingv interrupted.the solenoid serves as a choke coil and limits the current to apredetermined value, thus preventing an excessive current under overloador short-circuit conditions that would be destructive to thecircuitbreaker-switch blade 22 and the contact 25.

If now the switch handle 3 be operated, the

first quarter turn will simply open the snap switch, the next quarterturn will cause one AAJ the circuit, the latch controlled circuitbreaker may be readily manually set by simply llO . these casings ma thecircuit breaker blade 22, throughout an indefinite number of makes andbreaks of .has the usual casing designated 60 while the latch controlledcircuit breaker onthe other side of the base may be covered by asuitable casing G2. Convenient means of securing consist of a pluralityof ears 63, registeringwith bosses 64 of the plate 2 provided withopenings to receive suitable bolts or like securing devices. l

I am aware of various maximum current load automatic cutout devicescombined with service switch constructions and particularly thedisclosures of the patent to Perkins #287,321 of October 23, 1883, andthe disclosure of an automatic opening and closing device having amagnetically actuated detent i in the Drake Patent `:;#569,960 ofOctober My present effort has been to co-ordinate the mechanisms of a.magnetically controlled circuit breaker and a snap switch of modernconstruction in compact manner whereby the snap switch may be operablein the usual manner and the operating means therefor may function onlyto close the circuit breaker without influencing the functioning of thecurrent breaker opening means in the event lof a prevailing overloadcondition in the circuit controlled by the device'. A

I claim f 1. An electric circuit controlling device.

lcomprising separable contacts.y means for .closing the contacts,latching mechanism for holding the contacts closed, a solenoidv and corefor releasing said latch, a manually operable rotary member foractuating the closing means, a separate switch actuated by said manuallyoperable member through successive makes and breaks. independently ofIsaid contacts and a. normally closed bimetallic thermostatic switchconnected in series with said first named contacts and the contacts ofthe last named switch.

2. An electric circuit controlling comprising a circuit breaker tendingto open, a. latch for holding it closed, a solenoid connected withl thelatch, a manually operated switch,fmeans for connecting it to thecircuit breaker, whereby movement of said y switch may close the circuitbreaker and becomedisconnected while the'circuit breaker remains closed,electric connections through the solenoid whereby it may be responsiveto abnormal circuit conditions to release the device latch and anormally closed bimetallic thermostatic switch connected in series withvthe contacts of the circuit breaker and switch and bridging theconnections of the solenoid.

, 3. The combination with a circuit breaker,

of yielding means tending to open it, a. `latch for holding it closed,an electro-responsive control device for releasing the latch, a manuallyoperated switch having mechanicalmeans for closing the circuit breakerand placing it under the control of the latch, electrical connectionsthrough lthe circuit breaker and manually operated switch for connectingthe contacts thereof in series, a normally closed bimetallicthermo-responsive bar normally carrying the current and adapted to openthe circuit under abnormal conditions, and thereby cause the fullcurrent of the circuit to pass through the control device. 4. Thecombination with a circuit breaker, of yielding means tending to openit, a latch for holding it closed, an electro-responsive control devicefor releasing the latch, a manually operated switch having mechanicalmeans-for closing thecircuitbreaker and placing it u nder the control ofthe latch, electrical connections through the circuit breaker andmanuallv operated switch for connecting the contacts thereof in series,a bimetallic thermo-responsive bar normally carrying the current andadapted to open the circuit under abnormal circuit conditions, and shunti connections around said bar through thecontrol device to renderit'active momentarily when said bar is in open position.

-5. The combination with a circuit breaker,

-an electro-responsive means causing it to open 6, The combination witha circuit breaker,

an electro-responsive means causing it to opened and a. manuallyoperated switch 1nv series, with the circuit breaker and adapted to betemporarily mechanically lccuinected to the circuit breakerfor closingit and to be disconnected therefrom during the normal 1 operationof theswitch, said electro-responsive means including a bimetallic thermo-vresistance bar adapted to normally carry the drrent but to open thecircuit under abnormal conditions, and a magnetic solenoidhaving'electric connections shunting around the bar.

7. In a device of the character described, the combination of a handoperated revolving snap switch, a circuit breaker switch in seriestherewith and adapted to be closed by a revolving movement of a manuallyoperated member of the snap switch and having electro-responsive meansfor opening it automatically, and a normally closed self-closing circuitbreaker governing the circuitand responsive to overload to open thecircuit and thereby cause the electro-responsive means to open thecircuit breaker.

8. An electric circuit controlling device comprising manually separablecontacts and other automatically separable contacts, a manually operablemember for closing both sets of contacts, means connecting all of saiding normally contacts in series, a latching mechanism for holding theautomatically separable contacts closed, a magnetic device for trippingthe latching meclmnism, said magnetic device beelectrically -connectedin multiple relative to the means connecting the contacts in series, anda thermostatic switch connected in series with said contacts, bridgingthe connections for the magnetic device,

whereby the highly magnetic device will be in series with the contactswhen the thermostatically operated switch is open.

9. In a device of the character described, the combinataion of a basemember, a snap switch mechanism supported on one .side

thereof, a circuit breaking device mounted on the opposite side of thebase member, an operating member extending throughfthe base, and meansmounted on the operating member for closing and opening the snap switchand for closing the circuit breaker.

10. In a device of the character described, the combination of a snapswitch mechanism,

- a base formed of insulating material supporting the snap switchmechanism on one side thereof, a separable pair of contacts comprising acircuit breaker mounted on the opposite side of the base and in serieswith the switch mechanism, an operatingtmember extending through thebase, means mounted on the operating member for actuating the snapswitch mechanism for closing the contacts 'of the circuit breaker, alatch mechanism mounted on the base adjacent the separable conbreaking.device mounted on the opposite side tacts of the circuit breaker formaintaining them in closed relation, a magnetic device for tripping thelatch mechanism, a self-closing circuit breaking device connected inseries with said contacts and a shunt connection for the magnetic devicebridged by the self-closing device. n

11. In a device of the character described, the combination of a snapswitch mechanism mounted upon a base formed of insulating material, acircuit breaker having the contacts thereof connected in series withcontacts of the snap switch mechanism, the circuit breaker being mountedon the opposite side of the base'fan operating member in the form of arevoluble stem extending through the base for closing and opening thesnap switch contacts and for closing the contacts in the circuitbreaker, a magnetically released detent mechanism for latching thecircuit breaker contacts in closed position including a solenoid, and abimetallic thermostatically actuated circuit breaking device connectedin series with the contacts and bridging a shunt connection for thesolenoid, said operating member carrying means for closing the separablecontacts ofthe circuit breaker consequent to operating movement thereof.

12. In a device of the character described, the combination of a snapswitch mechanism, a supporting base therefor formed of insulatingmaterial, 4an operating member having a resilient connection with themovable contacts of the snap switch mechanism, said connection being inthe form of a spring whereby the spring may be tensioned to actuate thecontacts, a circuit breaker mounted on the opposite side of the base,means actuated by the operating member and extending'through the basefor closing the circuit breaker contacts during the spring tensioningmovement of the operating member, and automatically actuated detentmechanism for normally maintaining the circuit breaker contacts closed.

13. An electric circuit controlling device comprising manually separablecontacts and other automatically separable contacts, a manually operablemember for closing both sets of contacts, means connecting all of saidcontacts in series, a latching mechanism for holding the automaticallyseparable contacts closed, a magnetic device for tripping the latchingmechanism, said magnetic device beina normally electrically connected inVmultlple, relative to the means connecting the contacts in series, anda self-closing and opening circuit breaking device normally closed andconnected in series with -said contacts, bridging the shunt connectionfor the magnetic device.

.14. In a device of the character described, the combination of a snaswitch mechanism, a. base member supporting the snap switch mechanism onone side thereof, a circuit of the base member, an operating memberextending through the base and arranged to operate the snap switch, anda cam mounted on the operating member for closing the circuit breakercontacts.

15. In a device of the character described, the combinationlof a snapswitch mechanism, a base formed of insulating material supporting thesnap switch mechanism, a separable pair of contacts comprising a circuitbreaker mounted on the opposite side of the base, an cperatin member forthe snap switch extending t rough the base, a spring mounted on theoperating member for actuatin the snap switch mechanism, a cam carriedythe operating member for closing the contacts of the circuit breakera'iatch mechanism mountedon the base ad]acent the separable contactsofthe circuit breaker formaintaining them* in closed relation a magneticdevice for tripping the latch. mechanism, elec'- trically. conductivemeans connecting the snap switch mechanism contacts and the conp ing thetrip coil and responsive to variations in the current through thecircuit breakerI to open the shunt circuit under predetermined currentconditions.

17. The combination with a circuit breaker having a current-responsiveand inductivel current-limiting trip means 1n series wit the c1rcu1tbreaker, of a current-responsive resetting' device inseries with thecircuit breaker and normally shunting the trip means andresponsiveto'variations in the current through the circuit breaker toopen the shunt circuit under predetermined current conditions. v t t Intestimony whereoffIhereunto aix my signature.l

JOEL R. COOK.

